The invention relates to a method for producing a multiplicity of open-type disposable incontinence diapers for adults, having a diaper main part and front and rear diaper side parts attached thereto. Disposable incontinence diapers of this type are known and have a main part, consisting of a front region, a rear region and a crotch region that is located in between in the longitudinal direction and comes to lie between the legs of a user, wherein the main part usually already comprises an absorbent core, and having four diaper side parts that are separate from one another, are attached to the rear region and the front region on both sides and which extend in the transverse direction beyond lateral longitudinal edges of the main part and connect the front region and the rear region together in the put-on state of the article.
The diaper side parts are preferably attached directly to the diaper main part, that is to say the chassis of the sanitary article, on both sides in a cut and place method. This manufacturing technology makes it possible to manufacture the diaper side parts from a different raw material than the central diaper main part of the sanitary article. For example, the diaper side parts may be configured in an air-permeable manner, whereas the central diaper main part may be formed in a substantially moisture-impermeable manner.
The most efficient and simplest, and also most cost-effective, shape of the diaper side parts from a manufacturing point of view is the rectangular shape. This allows the materials forming the diaper side parts to be transported during production in the form of an endless web of flat material from which the diaper side parts are then severed transversely to the machine direction. There are virtually no offcuts in this case.
However, it has been shown that, particularly when the diaper side parts are formed in the otherwise advantageous rectangular shape, when the sanitary article is being put on and while it is being worn, the problem sometimes occurs that the attached diaper side parts can tear in the region of the lateral longitudinal edges of the diaper main part. It has specifically been shown that, when users put on the sanitary article, they tend to exert a pull, obliquely to the transverse and longitudinal direction of the sanitary article, on the diaper side parts that extend extremely far in the transverse and longitudinal direction in the case of incontinence articles for adults, this being shown in FIG. 1 by way of an obliquely upwardly directed arrow. In such cases, it is possible for diaper side parts to tear along the lateral longitudinal edges of the diaper main part, with the tear propagating from the transverse edge, facing the crotch region, of the diaper side part. Therefore, DE102010026643 (as yet unpublished) proposes providing the rear diaper side parts with contouring, such that a lower edge of the rear diaper side part is formed in a curved manner, that the lower edge has a convex portion, that the ratio of the length A of the lower edge of a rear diaper side part to the width B of the lower edge of a rear diaper side part is 0.4-0.9 and the ratio of the longitudinal extent E of an extreme point P of the convex portion to the transverse extent F thereof is 0.15-0.80. In one embodiment, DE102010026643 also already shows front diaper side parts having a concave leg-opening contour.
The present invention is thus based on the object of creating a cost-effective method that can be realized advantageously in terms of process technology, for producing such or similar disposable incontinence diapers.